What is a NoClassDefFoundError in java exception Reason and when will occur the error

What is a NoClassDefFoundError in java exception Reason and when will occur the error

NoClassDefFoundError is another common exception thrown by the class loader during the loading phase. The JVM specification defines NoClassDefFoundError as follows:

Thrown if the Java virtual machine or a ClassLoader instance tries to load in the definition of a class (as part of a normal method call or as part of creating a new instance using the new expression) and no definition of the class could be found.

The searched-for class definition existed when the currently executing class was compiled, but the definition can no longer be found.

Essentially, this means that a NoClassDefFoundError is thrown as a result of a unsuccessful implicit class load.

Note :
Another One Reason occure the “ NoClassDefFoundError”

Our Server have the jre 1.5 But you local system jre 1.6


Your local system class file generated by jdk 1.6 . that file uploed to the server . Then show the error. Because server have jdk 1.5. So version one problem.


Example Error Code

500 Servlet Exception
java.lang.NoClassDefFoundError: yellowpages/helper/AllCategoryDAO
at yellowpages.action.AllCategoryAction.execute(AllCategoryAction.java:27)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:413)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:225)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1858)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:446)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:114)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:181)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:266)
at com.caucho.server.hmux.HmuxRequest.handleRequest(HmuxRequest.java:435)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:602)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:690)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:612)
at java.lang.Thread.run(Thread.java:619)

Subject	Written By	Posted
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Thamodara Jegan	09/02/2005 03:08AM
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Sridevi Aruncahalam	11/28/2005 06:25AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	LuChen Lo	12/16/2005 11:45AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	LuChen Lo	12/16/2005 12:13PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	karthicraj rajendran	08/10/2009 02:27PM
Class.forName("com.mysql.jdbc.Driver"); con=DriverManager.getConnection("jdbc:mysql://lo calhost:3306/karthicraj","mysql","mysql");	karthicraj rajendran	08/10/2009 02:33PM
Re: Class.forName("com.mysql.jdbc.Driver"); con=DriverManager.getConnection("jdbc:mysql:// localhost:3306/karthicraj","mysql","mysql");	karthicraj rajendran	09/10/2009 11:15AM
Class.forName("com.mysql.jdbc.Driver"); con=DriverManager.getConnection("jdbc:mysql:// localhost:3306/karthicraj","mysql","mysql");	karthicraj rajendran	09/10/2009 11:32AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Mani Mani	08/12/2009 06:15AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Oliver f	09/25/2007 04:22PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Alina Apes	06/02/2009 11:53AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	jeevan reddy	05/31/2011 08:02AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	irfan u	04/20/2007 12:14AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Chandra G	07/31/2007 09:01AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	isuru udayanga	10/29/2008 07:17PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	sourabh sharma	01/08/2010 12:28AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	ram kumar	02/12/2010 11:00PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	amarjeet kumar	04/04/2011 01:47AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	suryaprakashnaidu pattipati	05/07/2010 01:36AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	gaurav gulanjkar	12/03/2010 10:52AM
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Alex Burno	03/16/2006 07:57AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	jayaraj selvakumar	09/28/2007 04:20AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Eman Hossny	11/29/2007 04:01PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	subari	04/01/2006 05:23AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Doni Osmon	01/04/2007 08:56PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Vincent Hughitt	05/06/2007 03:15PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	PraveenKumar Subramanian	11/13/2007 04:05PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Srinivas Marripudi	11/30/2007 11:56AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Amlan Banerjee	03/20/2010 11:48AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	arvind M	05/26/2010 07:46AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	kiran c	03/29/2008 10:53PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Tracey Bain	05/17/2007 03:18AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	khushboo kapoor	02/06/2008 02:03AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	rfg gxdg	04/22/2008 12:35AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Caesar Kennedy Olima	05/12/2008 11:22AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	aye seint	05/15/2008 12:23AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Fernando Mendoza	05/21/2008 10:50PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	wenbin Tang	07/09/2010 02:07AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Aimable Ruhumuliza	07/04/2008 11:13AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	vysakh kay	08/13/2010 09:15AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	ramesh babu	07/28/2008 11:07AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	subash thirimanna	12/14/2008 08:25PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	rekha jayaprakash	03/14/2009 12:59AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Kent Vanninen	08/11/2009 11:51AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	ramesh kumar	09/03/2009 07:37AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Gabriel Lopes	12/04/2009 08:15AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	amar singh	05/24/2010 09:31AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	tanusri reddy	05/24/2010 10:41PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	teresa du plessis	06/29/2010 08:18PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	M.J. S.	07/13/2010 02:42PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Aboobakkar Siddiq	10/04/2010 05:55AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Mohammad Amin Sarkandi	03/12/2011 04:56PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	cabbeen long	03/13/2011 08:29PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	anjan rao	10/08/2010 08:16AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Thomas Frank	11/08/2010 01:11PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Rahul Shingala	02/21/2011 04:32AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	zhang chunyan	03/14/2011 04:53AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	deni borin	03/17/2011 08:00AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	luke archer	03/28/2011 03:39PM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Saniya Deshpande	04/01/2011 12:17AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	price pk	06/02/2011 03:35AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	roopa kumar	06/16/2011 03:44AM
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	Muhammad Afzal	06/21/2011 02:10AM
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	keerthana gopal	07/01/2011 01:16AM
Re: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver	keerthana gopal	07/01/2011 01:31AM